James Lomas-Holt leads on embodied carbon in our Manchester sustainability team, helping clients to achieve their sustainability goals. In this article, we look at how to reduce embodied carbon in construction through advanced modelling and design.

James joined Ridge in 2020 through our acquisition of Scott Hughes Design, after spending seven years progressing through the ranks in the sustainability team and having recently been promoted to Associate. Over his professional career, James has gained extensive experience in advising clients on how to achieve sustainability goals, whether that be BREEAM, under which he holds an assessor and AP license, Net Zero Carbon in Construction, embodied carbon, or other bespoke solutions. James works as part of the larger Ridge Sustainability team delivering Net Zero Carbon (NZC) solutions nationally.

Delivering Net Zero Carbon at Ridge

At Ridge we help our clients identify and deliver NZC both for operational and embodied carbon, utilising our extensive multi-disciplinary skills to support our clients in decarbonising their assets across new construction and retrofit in line with funding and planning requirement and ESG policies.

James is the lead Embodied Carbon Analyst, in our Manchester office, helping his clients to achieve NZC – in construction – through working with the design team from the early design stages to advise and encourage the use of materials with a reduced carbon impact.

Embodied Carbon

• ‘Embodied carbon’ refers to the carbon emissions associated with the production, supply and construction of materials which make up a new building or infrastructure project. The scope of emissions also includes in-use maintenance, repair and replacement of materials over the life of the scheme, and also the eventual end-of-life impacts.
• ‘Upfront’ embodied carbon focuses specifically on the impacts up to practical completion, with no further consideration of in use or end of life impacts.
• 11% of global greenhouse gas emissions are attributable to embodied carbon in the built environment (Bringing embodied carbon upfront, World Green Building Council, September 2019).

How to reduce upfront embodied carbon

• Model, monitor and minimise upfront embodied carbon as early as possible in the design process
• Look for lower carbon alternatives to proposed materials.
• Reduce or remove reliance on Portland cement in concrete mixes (i.e. through specifying cement replacement such as fly ash or GGBS).
• Maximise recycled content of materials (e.g., recycled aggregates from local sources in place of quarried aggregate, higher recycled rates in structural steel).
• Use products with Environmental Product Declarations (EPDs).
• Reduce construction emissions e.g. AdBlue fuel additives, biofuels, electricity.
• Utilise off site modular construction.

The UK Green Building Council (UKGBC) has developed a framework definition for Net Zero Carbon buildings, which sets out the process for demonstrating that a development has achieved Net Zero Carbon status. This can be split into two parts currently: Net Zero Carbon – in construction, Net Nero Carbon – in operation. A third route – Net Zero Carbon – whole life, is currently under development by the industry. Ridge is currently working with a wide variety of clients to demonstrate compliance with these definitions.

Net Zero Carbon – Construction: Life Cycle Assessment (LCA) modelling software is used to build a model of the development, using information on materials and quantities of the scheme (supplemented by industry recognised benchmarks and assumptions). The process should commence as early as possible in the development process, so impacts are factored into design decision making process and the opportunity to reduce carbon is maximised. The carbon model is monitored and updated throughout design and construction, with the final, RIBA Stage 6 total being used to understand the actual footprint of the scheme up to practical completion. The project team also set out how the project has been designed to reduce operational energy demand and increase on-site renewable energy supply.

Net Zero Carbon – Operational Energy: During design and construction, the scheme design incorporates features to reduce the expected energy demand. Considerations include improving the building fabric and other passive design measures, increasing building systems efficiency and providing improved energy management techniques. The project also reviews the provision of renewable energy supply, prioritising on-site sources where feasible. Once the scheme has been in operation for a year, the carbon impacts of the actual energy usage and offsets are verified using energy supply data, this must be repeated annually to maintain the declaration status.

Both above routes prioritise reducing the calculated carbon impacts as a priority, but where emissions cannot be eliminated carbon offsets are required to ensure a net zero carbon balance. Once the balance has been achieved, a scheme can be declared as Net Zero Carbon in line with the relevant definition.

Ridge is currently helping clients design and deliver against their Net Zero objectives on a number of projects across the country, including UKGBC NZC In Construction modelling and verification. One example is Units 11 & 12 Ma6nitude – Two new industrial units located at Ma6nitude Business Park in Middlewich delivering 190,000 sq ft of industrial space to Net Zero Carbon in Construction (pictured below).

For more information, please contact one of our specialists listed below, and look out for our next post which will provide more in-depth information on Net Zero Carbon in Operation.

James Lomas-Holt
Associate, Sustainability
jameslomas-holt@ridge.co.uk

Kat Adair
Associate, Sustainability
katadair@ridge.co.uk